Container with reclosable pull-out pouring spout

ABSTRACT

A container for packaging comminuted dry products or the like is provided which has a self-contained reclosable pull-out pouring spout. The container is formed from a single blank of sheet material and, when initially setup, forms a sift-proof container having a flat top and with the pouring spout in a retracted closed position.

Elnited States Patent [1 1 Uark July 3, I973 [54] CONTAINER WITH RECLOSABLE 2,132,925 10/1938 Bensel 229/17 R U T O I SPOUT 2,811,297 10/1957 Maxon 229/17 R 3,003,673 10/1961 Clark et al. 229/17 R [76] lnventor: David A. Clark, 250 N. Maguire No. ,17 ,090 4/1965 Connell 229117 R 107, Tucson, AIlZ. 85710 3,477,632 11/1969 Donahue 229/17 R [22] Filed: June 1, 1971 Appl. No.: 143,697

Related US. Application Data Continuation-impart of Ser. No. 124,332, March 15, 1971, abandoned.

References Cited UNITED STATES PATENTS 10/1962 Harms 229/39 R X Primary Examiner-Davis T. Moorhead Attorney-R. E. Zimmerman [5 7] ABSTRACT A container for packaging comminuted dry products or the like is provided which has a self-contained reclosable pull-out pouring spout. The container is formed from a single blank of sheet material and, when initially setup, forms a sift-proof container having a flat top and with the pouring spout in a retracted closed position.

10 Claims, 13 Drawing Figures 9 I l I! 6 4T l' 22 I l I H I /3 II /4 i i I /7 /8 I /9 H 'i I I IV I I m i l 2 Sheets-Sheet l A TTORNE Y AV/D A. CLARK gygh, M M) Patented July 3, 1973 Patented July 3, 1973 .2 Sheets-Sheet 2 I INVEN TOR. DA W0 A. CLARK -im M m4...)

ATTORNEY CONTAINER WITH RECLOSABLE PULL-OUT POURING SPOUT This is a continuation-in-part of my application, Ser. No. 124,332, filed Mar. 15, 1971 and entitled CON- TAINER WITH IMPROVED STRUCTURE AND PULL-OUT SPOUT, now abandoned.

BACKGROUND OF THE INVENTION Various containers or cartons with pouring spouts have heretofore been provided; however, because of certain design characteristics they have been beset with one or more of the following shortcomings: (a) the pouring spout was difficult to open and when the container was initially closed, accidental leakage of the accommodated product frequently occurred in the vicinity of the spout even though the container was subjected to only normal handling; (b) the configuration of the container blank was such that an inordinate amount of material waste resulted during formation of the blank; (c) the pouring spout was a separate component formed of metal or plastic and required a separate operation in affixing to the container or blank therefor; (d) where the container had a self-contained retractable pouring spout, an effective leak-proof container having a flat top could not be formed utilizing known techniques and folding equipment; (e) the container was not capable of being shipped to the customer in a collapsed state and thus, in order to avoid the high costs of shipping empty set-up containers, it was necessary that the containers be manufactured at a site in close proximity to the customers filling operation; (f) the setting up of thecontainer having a self-contained pouring spout required the use of costly and complex equipment not customarily found on high speed packaging lines; and (g) the pouring spout, when selfcontained, severely restricted the style of container on which said spout could be incorporated.

SUMMARY OF THE INVENTION Thus, it is an object of this invention to provide a foldable sift-proof container having a self-contained reclosable pull-out pouring spout which is not beset with the aforenoted shortcomings of the prior structures.

It is a further object of this invention to provide a container of the type described which is of simple, yet sturdy construction, is capable of accommodating a wide variety of dry products, is capable of withstanding normal, though sometimes abusive, handling, prior to being initially opened, without causing accidental leakage of the product from the container; and is capable of being setup with high speed automatic equipment, the operation of which is well known in the packaging field.

It is a still further object of this invention to provide a folding container having a self-contained reclosable pull-out pouring spout wherein close manufacturing tolerances particularly with regard to the components of the pouring spout, are not required in order to provide an effective sift-proof container when the spout is in a closed retracted position.

It is a still further object of this invention to provide a folding container of the type described wherein the pouring spout thereof may be initially opened and reclosed by simple manual manipulations.

It is a still further object of this invention to provide a tamper-proof folding conatiner with a self-contained reclosable pull-out pouring spout.

It is a still further object of this invention to provide a folding container of the type described which, when in its initially closed position, has no outwardly protruding portion of the pouring spout which might cause accidental opening of the spout or would interfere with compact packing of a plurality of loaded containers for storage or shipping.

It is a still further object of this invention to provide a blank for a folding container of the type described which has a simple peripheral configuration thereby enabling like blanks to be cut from a sheet or web of blank material with but a minimum of material scrap resulting.

It is a still further object of this invention to provide a folding container having a self-contained reclosable pull-out pouring spout wherein the latter will remain in a reclosable retracted position without requiring interlocking or bonding of various components of the container.

It is a still further object of this invention to provide a folding container of the type described, wherein the pouring spout includes a component which facilitates initial or repeated opening of the spout and aids in retaining the spout in a closed, retracted position.

Further and additional objects will appear from the description, accompanying drawings, and appended claims.

In accordance with one embodiment of the invention, a folding container for a comminuted dry product is provided which includes a self-contained reclosable pull-out pouring spout formed in the top portion of the container. The container is formed from a single blank of sheet material and comprises side and end walls having closure flaps foldably connected to the upper end limits of the container walls. The closure flaps have adjacent ends thereof foldably connected. The closure flap connected to one end wall and the adjacent portions of the closure flaps connected to the side walls form the components of the pouring spout. The one end wall closure flap includes a first triangular section having one side edge thereof connected to and substantially coextensive with the upper end limit of the one end wall, and second triangular sections disposed on opposite sides of the first section and foldably connected to the remaining side edges of the first section. A second side edge of each second section is foldably connected to the adjacent end of the closure fap connected to the upper end limit of a side wall. One of the closure flaps connected to a side wall is adapted to overlap the other closure flap, when the top of the container is closed, and substantially span the distance be tween the side walls. The overlapping closure flap is provided with a tear line in spaced substantially parallel relation with the folding axis of the closure flap. The tear line extends from the end of the closure flap connected to one of the triangular second sections.

The free edge of one of the closure flap triangular second sections is provided with a tab which is substantially coextensive with the free edge and is adapted to be sandwiched between the closure flap connected to one side wall and the other triangular second section when the pouring spout is folded into a closed retracted position.

DESCRIPTION For a more complete understanding of the invention reference'should be made to the drawings wherein:

FIG. I is a perspective view of one form of the improved container shown in an initially closed condition.

FIG. 2 is an enlarged fragmentary perspective top view of the container of FIG. 1 showing the portion thereof incorporating the pouring spout in its initially closed retracted position.

FIG. 3 is similar to FIG. 2, but showing the pouring spout pulled out.

FIG. 4 is a fragmentary sectional view taken along line 4-4 of FIG. 2.

FIG. 4a is a fragmentary sectional view taken along line 4a-a of FIG. 2.

FIG. 5 is a plan view of the blank for the container of FIG. 1.

FIG. 6 is a fragmentary plan view of the bottomforming portion of a modified blank.

FIGS. 7-16 are fragmentary perspective views showing various Stages of forming the closed top of the container of FIG. 1.

FIG. 11 is a fragmentary end elevational view of the container of FIG. 1 and showing the pouring spout in its initially closed position.

FIG. 12 is a fragmentary perspective view of the top of the container showing the pouring spout in a reclosed position.

Referring now to the drawings and more particulary to FIG. I, an improved, rectangularly shaped foldable container or carton l is shown which is provided with a substantially flat top la which incorporates the reclosable pull-out spout, to be described more fully hereinafter. The container 1 is particularly suited for accommodating comminuted dry products, such as granulated detergents, grass seed, ice-melting salt, fertilizer, cake mixes, etc., wherein the entire contents of the container is not normally dispensed at one time. The size and shape of the container and the location of the pouring'spout thereon may vary from that shown without departing from the scope of the invention.

The container 1, in the illustrated embodiment, is formed from a blank of sheet material such as paperboard or the like, see FIG. 5. The type of sheet material to be used in forming the blank will depend upon the characteristics of the product to be accommodated in the container.

The blank includes panels A, B, C and D which are arranged in side-by-side relation and are interconnected along their elongated edges by foldlines l3, l4, and 15, respectively. Panels A and C define the side walls and panels B and D define the end walls when the blank is setup to form the container 1. A glue flap E may be connected by foldline 16 to the outer edge of panel I).

Connected by foldlines 21 and 22 to the upper edge of side wall panels A and C, respectively, are closure flaps 8 and 9. When the top 1a of container 1 is formed, as seen in FIG. I, flap 9 will be exposed and overlap flap 8 and be adhesively secured thereto. Each flap 8 and 9 is substantially coextensive with the upper edge of the side wall panel to which it is foldably connected. In the illustrated embodiment, the length of flap 9 mea sured perpendicular to foldline 22 is substantially equal to the spacing between foldlines l3 and 14 connecting end wall panel B to side wall panels A and C.

One end 9a of closure flap SP is provided with a pair of foldlines 2 which converge from the corners of the flap so as to define a triangular area I. The angle ineluded by foldlines 2 is bisected by a tear line 3 which extends to the adjacent end of the flap 9.

Connected by foldlines 23 and 24 to the upper edges of end wall panels B and D, respectively, are triangluar segments 4', 5', and 6 and 4, 5, and 6, see FIG. 5. Segment 5' or 5 is centrally disposed with respect to the remaining segments 4' and 6' or 4 and 6 and has the lower side thereof defined by foldline 23 or 24. Corresponding sides of segment 4' and 6' or 4 and 6 are foldably connected to the remaining two sides of triangular segment 5' or 5.

A second side 6a of segment 6 is foldably connected to the lower portion'of the end 9a of flap 9. The foldline connection constitutes an extension of foldline 14. The remaining side 6b of segment 6 is formed by a cut and is substantially coaxial with tear line 3 formed in the triangular areal of flap 9. In a like manner, segment 6' is connected to the opposite end 9b of the flap 9.

Triangular segment 4 has a second side 4 a thereof foldably connected to an adjacent end of closure flap 8. The foldline connection between flap 8 and segment 4 constitutes an extension of foldline 13 which joins panels A and B. In the preferred embodiment, the remaining side of segment 4 is provided with a tab or tongue 4T which projects beyond the side edge 6b of segment 6, see FIG. 5. If desired, however, such tab 4T may be formed on the edge 6b of segment 6 rather than as shown in the drawings. The function of tab 4T, in either case, will be described more fully hereinafter.

Flap 8 has a triangular segment 7 formed at the end thereof which is foldably connected to and is substantially a mirror image of triangular segment 4. Segment 7, in turn, is substantially the same shape as half 7 of the triangular area I defined by the tear line 3 so that, when flaps 8 and 9 are in overlapping realtion, area 7 will be in superposed relation with respect to segment 7 and be adhesively secured thereto.

Segments 4, 5', and 6' are similarly arranged, except that segment 4 has one side thereof foldably connected to an adjacent portion of glue flap E. The remaining side of segment 4' is provided with a projecting tab 4'T.

As seen in FIG. 5, foldlines 21, 24, 22, and 23 are coaxially aligned and are disposed perpendicular to foldlines 13, 14, 15, and 16. Furthermore, the length of flap 8 measured normal to foldline 21 is approximately one half the length of flap 9.

Foldably connected to the lower edge of panels A-D may be conventional bottom closure flaps l2, 110, II, and 25, respectively. In such an arrangement, flap ll would be exposed and overlie and be adhesively secured to flap I2 and the latter, in turn,.would be adhesively secured to and overlap flaps 1.6 and 25.

If desired, however, flaps 8B and 9B and triangular segments 43, 5B, and 6B; and 4B, 5B, and 68' might be substituted for the bottom closure flap 12, ll, 10 and 25, respectively, see FIG. 6. In the latter arrange ment, a projecting tab 4TB or 4TB would be formed on either triangular segment 48, 4B, 6B, or 68'. With the modified blank shown in FIG. 6, the top and bottom of the container would be closed in a like manner and thus, only closing of the top Ia of the container will now be described.

The blank will initially be folded so that glue flap E will be secured by adhesive or hot melt to the inner surface of panel A. The blank, in such a state, assumes a collapsed tubular condition and normally remains in such a condition until the container is to be setup for filling. In FIG. 7, the collapsed tubular blank is squared so as to form a tube whereby panels A and C and panels B and D are disposed in opposed spaced relation and define the cavity in which the product is to be deposited. For purposes of describing the closing of the top of the container, it is assumed that the bottom has already been formed and that the product has been deposited within the cavity.

Initially the central triangular segments 5 and 5' are pressed inwardly towards one another about foldlines 24 and 23, respectively, as axes, see FIG. 8. Because the segments 5 and 5 are foldably connected to adjacent segments 4 and 6 and 4' and 6' which, in turn, are foldably connected to the ends of the closure flaps 8 and 9, all of the segments and closure flaps will commence to fold inwardly. As inward force continues to be exerted on the segments 5 and 5', segments 4, 4' and 6, b will fold back under the respective ends of closure flaps 3 and 9. In FIG. 9 it will be noted that tabs 4T and 4"1" project from beneath flap 8 and each is guided by the undersurface of flap 9 into an adjacent V-shaped pocket P, see FIG. 9, formed as the triangular segment 6 or 6 is folded back under the end of the outer closure flap 9. Upon closure flap 9 reaching a substantially horizontal or fully closed position, each projecting tab will become wedged or sandwiched between the underside of the outside flap 9 and the segment 6 or 6', see FIGS. d and 4a. Because tab 4T extends a substantial distance beyond tear line 3 and the edge 6b of segment 6, the tab 4T prevents leakage of the product in the vicinity of the tear line 3 and edge 6b, notwithstanding, that the disposition of said tear line and edge might not be in substantial vertical alignment. Thus, manufacturing tolerances, with respect to the location of the tear line 3 and edge 6b of the segment 6, may be less exacting than might otherwise be the case and still enable the container to be substantially leak-proof in the vicinity of the retracted pouring spout when the container is in its initially closed position.

To facilitate insertion of the tab 4T or 4'T into the adjacent pocket F during closing of the top, the narrow ends of each tab may be rounded or bevelled, as shown. It will also be noted that the edge 6b of segment 6 does not engage in abutting relation any portion of segment 4 as is the case in various prior art structures (e.g., in U.S. Pat. No. 3,120,335 the cut edges of the fold-back panels 60 and 61, FIGS. 7-9 assume an abutting relation). Thus, sliding of the tab 4T into pocket P is a smooth and unobstructed operation permitting closing of the top to be readily accomplished either manually or by high speed automatic or semi-automatic folding apparatus.

In instances where the tab is formed on the triangular segment 6 rather than segment 4, as shown, the aforedescribed folding procedure is followed, except that the tab is inserted into a V-shaped pocket formed between closure flap 8 and the folded back segment 4. In most instances, it is preferred that the tab 4T be formed on segment 4 rather than segment 6.

When the container is in its initial fully closed condition, the top 1a assumes a substantially flat position, thereby facilitating stacking of a plurality of loaded containers for storage or shipping.

In order to open the top of the container so as to enable an extended pouring spout to be formed, as in FIG. 3, a fingertip is inserted under segment 6 and in substantial vertical alignment with tear line 3. Upon a relative upward movement of the fingertip, flap 9 will tear along tear line 3 while at the same time tab 4T will be withdrawn from the pocket P because the tab is not adhesively or otherwise secured to the underside of flap 9 or segment 6 or flap 8 or segment 4, whichever the case may be. The foldlines 2 formed on flap 9 enable the severed or torn portions 9 of the flap adjacent the tear line 3 to fold upwardly relative to the remainder of the flap 9. Once the torn portions 9 have been folded upwardly so that the tab 4T is removed from the pocket P, the tab will project upwardly, see FIG. 12, thereby enabling the tab to be readily grasped and pulled outwardly in a direction substantially parallel to the remainder of the top thereby causing the triangular segments 4, 5, and 6 to project outwardly and form a pouring spout, see FIG. 3. The segments 4, 5 and 6 will remain extended by reason of the upwardly folded torn portions 9' of flap 9.

To reclose the container, the center segment 5 is manually pushed inwardly until it passes the plane of end wall B of the container whereupon said center segment will automatically snap into an inwardly extending closed position, as seen in FIG. 12. The segment 5 will remain in its reclosed position until the tab 41 is once again pulled outwardly to form the pouring spout.

When the segments 4, 5, and 6 assume the reclosed position, as seen in FIG. 12, the segments 4 and 6 are disposed in a fold-back contacting relation with the un derside of the torn portions 9' of the flap 9 and thus, the contents of the container are concealed from exposure to dirt, dust, or other foreign material.

The configuration of the container blank, as seen in FIGS. 5 and 6, is simple and can be readily produced on conventional high speed scoring, slotting, and cutting equipment. Furthermore, a plurality of blank outlines can be arranged in nested relation on a sheet or web of blank material so that there is a minimum of material wastage. Where a large volume of blanks are being produced by automatic equipment, the amount of material wastage or scrap which results is an important cost factor.

Thus, it will be seen that an improved container and blank therefor have been provided wherein the container has a self-contained reclosable pull-out pouring spout. The improved container is substantially leakproof when in its initially closed condition. The improved container is of inexpensive, simple, yet sturdy, construction, and may be readily produced on conventional high speed equipment. The pouring spout of the improved container is so constructed that it will automatically remain in either its extended or retracted positions. Furthermore, the components of the improved pouring spout do not abut one another when the container is in its initially closed or reclosed positions and thus, manufacturing tolerances for the improved container need not be as carefully controlled as is the case with the prior structures.

I claim:

1. A folding container for comminuted dry products having a self-contained, reclosable pouring spout, said container comprising foldably connected side and end walls, and closure flaps foldably connected to the upper edges of said walls and initially overlapping one another to form a substantially flat, exposed top surface; said closure flaps including an outer flap connected to a side wall and overlying and being adhesively secured only to an inner flap connected to an opposed side wall, a triangular end flap having one side thereof connected to an end wall, and triangular connecting flaps foldably connected to the remaining sides of said end flap and to the adjacent ends of said outer and inner flaps; one connecting flap being provided with a unitary projecting peripheral tab; the outer flap having a substantial portion of the end thereof projecting beyond the folding connection between said outer flap end and the connecting flap; said end and connecting flaps extending inwardly in fold-back relation when said container is initially closed and said peripheral tab being freely slidable into a snugly sandwiched relation between a closure flap connected to one side wall flap and the connecting flap foldably connected thereto; said outer flap having the portion thereof overlying the end flap capable of being torn whereby said end and connecting flaps and said peripheral tab remain in unitary relation and are movable to extended positions to form the pouring spout.

2. The container of claim 1 wherein the projecting peripheral tab is formed on the triangular connecting flap connecting said inner closure flap and said end flap.

3. The container of claim 1 wherein the outer closure flap substantially spans the distance between the opposed side walls and is provided with a tear line extending endwise from the end of said outer flap which over- .lies the triangular end flap when said container is in an initially closed condition.

4. The container of claim 3 wherein said tear line extends in a direction substantially perpendicular to the foldline connection between said end flap and end wall, and terminates at the apex of said triangular end flap opposite said foldline connection.

5. The container of claim 4 wherein the inner edge of said inner closure flap is substantially aligned with said tear line.

6. The container of claim 4 wherein one edge of the second connecting flap is substantially aligned with the outer flap tear line when said container is in its initially closed condition.

7. The container of claim 2 wherein the underside of the outer flap and the connecting flap connected to said outer flap form a pocket in which only the peripheral tab of the other connecting flap is slidably disposed when said closure flaps are moved into overlapping relation to efiect initial closing of said container.

8. The container of claim 7 wherein the entire peripheral tab is slidably withdrawn from said pocket and exposed when said outer flap is initially torn said exposed tab being a handle to effect movement of said end and connecting flaps into extended pouring spout positions; said tab forming a portion of the extended pouring spout.

9. A blank of foldable sheet material for forming a container having pairs of side and end walls and closure flaps adapted when in one position of adjustment to form a pouring spout, said blank comprising side wallfonning and end wall-forming panels arranged in alternate side-by-side relation, an outer closure flap foldably connected to and substantially coextensive with the upper edge of one side wall-forming panel, an inner closure flap foldably connected to and substantially coextensive with the upper edge of a second side wallforming panel, a triangular closure flap disposed intermediate said inner and outer closure flaps, said triangular closure flap having a side thereof foldably connected to the upper edge of one end wall-forming panel, triangular connecting flaps foldably connected to the remaining sides of said triangular closure flap, one connecting flap having a second side thereof foldably connected to an end of said inner flap; the other connecting flap having a second side thereof foldably connected to an end of said outer flap, said outer flap end extending beyond the connection between said outer flap and said other connecting flap,- the second side of said other connecting flap being aligned with an elongated tear line formed in said outer flap, said tear line being in spaced substantially parallel relation with the folding connection between said outer flap and said one side wall-forming panel, and a projecting tab forming the third side of one of the connecting flaps; said tab and said one connecting flap being of unitary construction and forming a wall portion of the extended pouring spout when said blank is set up.

10. The blank of claim 9 wherein the end of said outer flap connected to said other connecting flap is provided with a pair of convergent foldlines extending from comers of the outer flap end and forming an apex,

one end of said tear line terminating at said apex. 

1. A folding container for comminuted dry products having a self-contained, reclosable pouring spout, said container comprising foldably connected side and end walls, and closure flaps foldably connected to the upper edges of said walls and initially overlapping one another to form a substantially flat, exposed top surface; said closure flaps including an outer flap connected to a side wall and overlying and being adhesively secured only to an inner flap connected to an opposed side wall, a triangular end flap having one side thereof connected to an end wall, and triangular connecting flaps foldably connected to the remaining sides of said end flap and to the adjacent ends of said outer and inner flaps; one connecting flap being provided with a unitary projecting peripheral tab; the outer flap having a substantial portion of the end thereof projecting beyond the folding connection between said outer flap end and the connecting flap; said end and connecting flaps extending inwardly in foldback relation when said container is initially closed and said peripheral tab being freely slidable into a snugly sandwiched relation between a closure flap connected to one side wall flap and the connecting flap foldably connected thereto; said outer flap having the portion thereof overlying the end flap capable of being torn whereby said end and connecting flaps and said peripheral tab remain in unitary relation and are movable to extended positions to form the pouring spout.
 2. The container of claim 1 wherein the projecting peripheral tab is formed on the triangular connecting flap connecting said inner closure flap and said end flap.
 3. The container of claim 1 wherein the outer closure flap substantially spans the distance between the opposed side walls and is provided with a tear line extending endwise from the end of said outer flap which overlies the triangular end flap when said container is in an initially closed condition.
 4. The container of claim 3 wherein said tear line extends in a direction substantially perpendicular to the foldline connection between said end flap and end wall, and terminates at the apex of said triangular end flap opposite said foldline connection.
 5. The container of claim 4 wherein the inner edge of said inner closure flap is substantially aligned with said tear line.
 6. The container of claim 4 wherein one edge of the second connecting flap is substantially aligned with the outer flap tear line when said container is in its initially closed condition.
 7. The container of claim 2 wherein the underside of the outer flap and the connecting flap connected to said outer flap form a pocket in which only the peripheral tab of the other connecting flap is slidably disposed when said closure flaps are moved into overlapping relation to effect initial clOsing of said container.
 8. The container of claim 7 wherein the entire peripheral tab is slidably withdrawn from said pocket and exposed when said outer flap is initially torn said exposed tab being a handle to effect movement of said end and connecting flaps into extended pouring spout positions; said tab forming a portion of the extended pouring spout.
 9. A blank of foldable sheet material for forming a container having pairs of side and end walls and closure flaps adapted when in one position of adjustment to form a pouring spout, said blank comprising side wall-forming and end wall-forming panels arranged in alternate side-by-side relation, an outer closure flap foldably connected to and substantially coextensive with the upper edge of one side wall-forming panel, an inner closure flap foldably connected to and substantially coextensive with the upper edge of a second side wall-forming panel, a triangular closure flap disposed intermediate said inner and outer closure flaps, said triangular closure flap having a side thereof foldably connected to the upper edge of one end wall-forming panel, triangular connecting flaps foldably connected to the remaining sides of said triangular closure flap, one connecting flap having a second side thereof foldably connected to an end of said inner flap; the other connecting flap having a second side thereof foldably connected to an end of said outer flap, said outer flap end extending beyond the connection between said outer flap and said other connecting flap, the second side of said other connecting flap being aligned with an elongated tear line formed in said outer flap, said tear line being in spaced substantially parallel relation with the folding connection between said outer flap and said one side wall-forming panel, and a projecting tab forming the third side of one of the connecting flaps; said tab and said one connecting flap being of unitary construction and forming a wall portion of the extended pouring spout when said blank is set up.
 10. The blank of claim 9 wherein the end of said outer flap connected to said other connecting flap is provided with a pair of convergent foldlines extending from corners of the outer flap end and forming an apex, one end of said tear line terminating at said apex. 